I went to college at Pitt, where the campus is basically just a part of Pittsburgh that has a slightly higher concentration of college buildings than other parts; in other words lots of non-college-student traffic, and also a very large amount of hoboes. Beggars make a very good living around campus. Some of them make more money than I will ever make. Many will "beg" during the day, and at night go home to a nice big house. So no one gets money from me, no matter how poor they look. Some other beggars there are weird 20-year-old dirty hitchhikers, and I don't give them money because they make me angry. A lot of other beggars use money to buy drugs or booze. They're not getting my money, for obvious reasons. A lot of other beggars are able-bodied but don't work. They don't deserve my money. Then there are the truly insane hoboes, like one guy on campus who wore 3 long coats all year round and had two huge dogs following him everywhere. If he asked me for money I'd run for my life.
One time someone asked my friend for money because he was so hungry he couldn't stand it. My friend went to McDonalds and bought him some coffee and food, and gave it to him. The beggar threw it in the trash and demanded money.